Suppose we have $(n,e)$ and the ciphertext $c$ where the public exponent $e$ is of the same length, 1023-bit, as the modulus $n$. It is also assumed that the factors of $n$ are balanced. The message is decrypted using CRT with small exponents but unknown to us, attacker. Is it possible to decrypt $c$ in such a scenario?

1 Answer
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There is a paper by Daniel Bleichenbacher and Alexander May called "New attacks on RSA with small secret CRT-Exponents" (you can find it under http://www.cits.rub.de/imperia/md/content/may/paper/crt.pdf). They are not quite able to break the RSA under your assumptions. I'm not aware of better results, but I didn't look at the list of articles citing this paper.